First discovered in 1964 in Montana,DEINONYCHUS was a bipedal carnivore with a large scythe-like claw on each foot. It is believed that these dinosaurs may have hunted in packs, due to the fact that many skeletons were discovered together. The brain was large for a dinosaur of this size, and it was probably quite intelligent. Because of this, its razor sharp claws and pack behavior, Deinonychus must have been one of the most terrifying animals to live in the Cretaceous period.